Set bound_fqn from ros_binding at manifest parse time

[bburda]

Summary

In manifest_only discovery mode, manifest_parser does not set bound_fqn on App entities. Since runtime_linker only runs in hybrid mode, apps in manifest_only mode have no FQN set, which breaks downstream handler/sampler code that needs it for log, fault, and configuration lookups.

Currently worked around with App::effective_fqn() (PR #258) which falls back to deriving FQN from ros_binding when bound_fqn is not set.

Proposed solution

manifest_parser should set bound_fqn from ros_binding at parse time when namespace is not wildcard "*":

// In manifest_parser, after parsing ros_binding:
if (app.ros_binding && !app.ros_binding->node_name.empty() 
    && app.ros_binding->namespace_pattern != "*") {
  std::string ns = app.ros_binding->namespace_pattern;
  if (!ns.empty() && ns.back() != '/') ns += '/';
  app.bound_fqn = ns + app.ros_binding->node_name;
}

This would:

• Make the data model consistent across discovery modes
• Allow removing the effective_fqn() workaround
• Prevent future code from accidentally using bound_fqn directly and missing manifest_only mode

Additional context

Relevant files:

• src/ros2_medkit_gateway/src/discovery/manifest/manifest_parser.cpp
• src/ros2_medkit_gateway/include/ros2_medkit_gateway/discovery/models/app.hpp - effective_fqn() workaround